1. Field of the Invention
The present invention relates to salts of poly unsaturated fatty acids with biguanides.
2. Technical Background
Diabetes mellitus has become pandemic and according to a forecast by the World Health Organization, there will be a sharp increase in the number of diabetic patients by the year 2030. This is an ominous forecast, because managing the long-term complications of diabetes, which include nephropathy, neuropathy, retinopathy, and cardiovascular complications, will have a serious impact on public health budgets. The hallmark of diabetes is chronically elevated blood glucose levels. It is also known that abnormally elevated glucose levels have an adverse impact on glutathione levels in key diabetic tissues. Furthermore, increased oxidative stress and increased production of reactive oxygen species are implicated under hyperglycemic conditions.
In spite of the early discovery of insulin and its subsequent widespread use in the treatment of diabetes, and the later discovery of and use of sulfonylureas, and thiazolidenediones, such as troglitazone, rosiglitazone or pioglitazone, as oral hypoglycemic agents, the treatment of diabetes remains less than satisfactory.
The use of insulin requires multiple daily doses, usually by self-injection. Determination of the proper dosage of insulin requires frequent estimations of the sugar in urine or blood. Treatment of non-insulin dependent diabetes mellitus (type 2 diabetes, NIDDM) usually consists of a combination of diet, exercise, oral hypoglycemic agents, e.g., thiazolidenediones, and, in more severe cases, insulin. However, the clinically available hypoglycemic agents can either have side effects limiting their use, or an agent may not be effective with a particular patient. In the case of insulin dependent diabetes mellitus (Type I), insulin administration usually constitutes the primary course of therapy.
The biguanide metformin is a known compound approved by the U.S. Food & Drug Administration for the therapeutic treatment of diabetes. The compound and its preparation and use are disclosed, for example, in U.S. Pat. No. 3,174,901. Metformin is orally effective in the treatment of type 2 diabetes. Metformin (N,N-dimethylimidodicarbonimidic diamide) is a biguanide, anti-hyperglycemic agent currently marketed in the United States in the form of its hydrochloride salt 1,1-dimethylbiguanide hydrochloride (Formula 1a).

Metformin hydrochloride can be purchased commercially and can also be prepared, for example, as disclosed in J. Chem. Soc., 1922, 121, 1790.
U.S. Pat. No. 7,973,073 B2 (Mylari) describes use of metformin R−(+) lipoate as being useful for treating diabetes or diabetic complications.
U.S. Patent Publication 2005/0165102 describes complexes of drugs (metformin being mentioned) with transport moieties (fatty acids being mentioned) to enhance absorption and control delivery of the drugs being used. Among the fatty acid complexing agents mentioned are caprate, laurate, palmitate and oleate.
U.S. Patent Publication 2005/0182029 describes metformin salts of lipophilic acid salts (fatty acids being mentioned), their pharmaceutical formulations, and methods of administering the metformin salts for the treatment of hyperglycemia.
According to United Kingdom Perspective Diabetes Study (UKPDS) (Clarke et al. Diabetologia, 2005, 48, 868-877), metformin therapy was cost-saving and increased quality-adjusted life expectancy. In the UKPDS, overweight and obese patients randomized to initial therapy with metformin experienced significant reductions in myocardial infarction and diabetes-related deaths. Metformin does not promote weight gain and has beneficial effects on several cardiovascular risk factors. Accordingly, metformin is widely regarded as the drug of choice for most patients with Type 2 diabetes.
Prediabetes is a syndrome. Many patients with type 2 diabetes and with a prediabetic condition known as metabolic syndrome suffer from a variety of lipid disorders including elevated triglycerides. The body uses triglycerides to store fat but high (>200 mg/dl) and very high (>500 mg/dl) triglycerides are associated with atherosclerosis which increases the patients risk of heart attack and stroke.
Incipient diabetes with impaired glucose tolerance is another prediabetic condition. Overall, type 2 diabetes and incipient diabetes with impaired glucose tolerance, are intimately intertwined with obesity, hyperlipidemia, including hypertriglyceridemia, and cardiovascular complications including arrhythmia, cardiomyopathy, myocardial infarction, stroke and heart failure. Clinically, pre-diabetes means that blood sugar level is higher than normal, but it's not yet increased enough to be classified as type 2 diabetes. Still, without intervention, prediabetes is likely to become type 2 diabetes over time
Also diabetic patients have impaired circulation which manifests itself in the slow healing of wounds in the foot and lower leg and puts the patient at risk for amputation.
Elevated triglycerides may be lowered by diet and exercise. Niacin and omega-3 fatty acids, commonly known as fish oil, are frequently used in the management of hypertriglyceridemia. Omega-3 fatty acids are unsaturated carboxylic acids which have a terminal double bond three carbons from the methyl terminus, the 3 position. Omega-3 fatty acids are commonly extracted from oily fish like salmon, mackerel and menhaden. They are also extracted from other marine sources like squid and krill. Omega-3 fatty acids are commercially available. The omega-3 fatty acids most commonly extracted from fish are eicosapentaenoic acid and docosahexaenoic acid. These compounds have been shown to have beneficial effects in treating obesity, arrhythmia, and myocardial infarction and have the structures:
eicosapentaenoic acid

and docosahexaenoic acid:

Resolvins are a special class of polyhydroxylated omega-3 fatty acids which possess potent antinflammatory and immunoregulatory actions. These biological actions of resolvins arc thought to play a significant role in cardiovascular and diabetic conditions.